Device for assisting the piloting in acceleration of an aircraft in taxiing in order to control its speed, related aircraft and method

ABSTRACT

A device is for assisting the piloting in acceleration of an aircraft in taking in order to control its speed. The comprises a control member, adapted to be actuated by a pilot from a neutral position to define a taxiing piloting command for controlling the speed of the aircraft and a central controller, adapted to operate pilot at least one engine of the aircraft to apply the taxiing command defined by the pilot. The taxiing piloting command is an acceleration or deceleration command of the aircraft during taxiing.

The present disclosure relates to a device for assisting the piloting ofan aircraft in taxiing, comprising a control member, able to be actuatedby a pilot from a neutral position to define a taxiing piloting commandfor controlling the speed of the aircraft and a central controller,adapted to pilot at least one engine of the aircraft to apply thetaxiing piloting command defined by the pilot.

The device for assisting the piloting of an aircraft in taxiing is, forexample, located in the cockpit of an aircraft, to assist the pilot incontrolling and piloting the speed of the taxiing aircraft as theaircraft rolls over the ground between its parking point and the runwayon which it takes off or lands.

BACKGROUND

Taxiing of the aircraft on the ground occurs at the beginning and end ofeach flight. It involves moving the aircraft on taxiways that aresometimes winding, on slopes, or in the presence of obstacles ortraffic.

In addition, taxiing must sometimes be carried out with time constraintslinked to take-off or landing slots, in order to free the runway asquickly as possible.

For pilots, taxiing therefore requires a significant workload, as theenvironment wherein the aircraft is operating is potentially dense, withobstacles in close proximity.

The pilot in charge of taxiing must therefore orientate himself on theterrain, monitor obstacles and traffic, and control the rolling speed ofthe aircraft.

In order to set and maintain the desired rolling speed, he must use twodifferent controls, namely the throttle and the brakes.

The throttle provides residual thrust to set and maintain the desiredrolling speed and the brakes allow the speed to be reduced if necessary.

The taxiing system is therefore not entirely satisfactory, particularlyin terms of passenger comfort and controllability.

The aircraft's engines are designed for flight and are therefore bynature sized to provide thrust far in excess of that required forrolling. (High) thrust and (slow on ground) response dynamics areproblematic for taxiing.

Sometimes the pilot may accelerate more than they he wishes, to allowthe aircraft to reach a target rolling speed. In addition, the pilot mayhave to brake suddenly. More generally, the pilot may have difficulty insetting the target rolling speed, resulting in uncomfortableacceleration and/or deceleration for the passengers.

Other systems do not have this problem; it is known for example fromUS2015210383 to equip the wheels of the aircraft with an independentdrive system, in particular an electric motor, and to provide the pilotwith a separate device for assisting the piloting in taxiing whichallows the electric motor to be controlled to move the aircraft at a setspeed.

In addition, taxiing piloting is carried out by piloting speed, whichcan still lead, in some cases, to inconvenience for passengers if theacceleration or deceleration is too significant.

SUMMARY

It is therefore an aim of the present disclosure to provide a device forassisting the piloting of an aircraft in taxiing that is simple toimplement on an aircraft, while increasing passenger comfort.

To this end, the present disclosure has as its subject matter a devicefor assisting the piloting of an aircraft in taxiing of theaforementioned type, characterised in that the taxiing command is anacceleration or deceleration command of the aircraft during taxiing.

The device for assisting the piloting of an aircraft in taxiingaccording to the present disclosure may comprise one or more of thefollowing features, taken alone or in any combination that istechnically possible:

the central controller is also able to pilot at least one braking memberof the aircraft to apply the acceleration or deceleration commanddefined by the pilot;

after the acceleration or deceleration command has been applied and thecontrol member is released, the control member is automatically returnedto the neutral position;

the neutral position is a fixed neutral with respect to a stroke of thecontrol member, the control member being automatically returned to thefixed neutral position;

the neutral position is a movable neutral position relative to a strokeof the control member, the control member being automatically returnedto the movable neutral position, or the movable neutral being movable tothe current position of the control member;

the control member is able to be moved to a maximum acceleration stopand/or to a minimum deceleration stop;

the maximum acceleration stop is able to move along the stroke of thecontrol member to limit the stroke of the control member as a functionof the current speed of the aircraft;

the minimum deceleration stop is adapted to be overcome in order toreach a maximum deceleration detent wherein the control member is lockedin position;

the engine is a propulsion engine for the aircraft, in particular a jetengine or a turboprop engine, suitable for exerting a thrust force onthe aircraft, and/or the engine is an electric motor for driving a wheelof the aircraft;

the control member comprises a movable lever for piloting at least oneengine of the aircraft capable of exerting a thrust force and/or forpiloting a member for modifying the drag of the aircraft capable ofreducing the mechanical energy of the aircraft, the device for assistingthe piloting of an aircraft in taxiing being capable of switchingbetween an inactive configuration during the take-off, flight andlanding phases and an active configuration during taxiing;

in the inactive configuration of the device for assisting the pilotingof an aircraft in taxiing, the control member is adapted to be moved bythe pilot to establish a command for varying the mechanical energy ofthe aircraft intended for the central controller, so that the centralcontroller pilots the or each propulsion engine and the or each dragmodification member, without piloting the or each braking member, and,in the active configuration of the device for assisting the piloting ofan aircraft in taxiing, the control member is suitable for being movedby the pilot in order to establish an acceleration or decelerationcommand for the aircraft during taxiing, intended for the centralcontroller, so that the central controller pilots each propulsion engineand optionally the or each braking member, advantageously withoutcontrolling the or each drag modification member;

the device comprises a button to activate the device for assisting thepiloting of an aircraft in taxiing, which is suitable for placing thedevice for assisting the piloting of an aircraft in taxiing in theactive configuration, the activation button being advantageouslyarranged on the movable lever;

the device comprises a button to deactivate the device for assisting thepiloting of an aircraft in taxiing, which is suitable for placing thedevice for assisting the piloting of an aircraft in taxiing in theinactive configuration, the deactivation button being advantageouslyarranged on the movable lever;

the device comprises a light-up display system capable of producing atleast one luminous indicator of the activation, operation and/ordeactivation of the device for assisting the piloting of an aircraft intaxiing;

-   -   the central controller contains a correspondence table or        formula associating an acceleration or deceleration value to be        controlled with each actuation of the control member;    -   the control member comprises a support, a lever mounted so as to        be movable in the support, and at least one position sensor,        intended to measure the position of the movable lever with        respect to the support, the position sensor being capable of        measuring an information representative of the position of the        movable lever and of transmitting the representative information        to the central controller at each moment so that the central        controller generates the command to accelerate or decelerate the        aircraft as a function of the gap between the current position        of the movable lever and a neutral position.

The present disclosure also has as its subject matter an aircraftcomprising a device for assisting the taxiing of an aircraft as definedabove, at least one engine capable of being piloted by the centralcontroller in order to apply the acceleration or deceleration commandestablished by the control member, the aircraft comprising at least onebraking member optionally also capable of being piloted by the centralcontroller in order to apply the acceleration or deceleration commandestablished by the control member.

The present disclosure also has as its subject matter a method ofpiloting an aircraft in taxiing, implemented with a device for assistingthe piloting of an aircraft in taxiing, the method comprising thefollowing steps:

actuation, by a pilot, of a control member of the device for assistingthe piloting of an aircraft in taxiing, from a neutral position in orderto establish a taxiing piloting command;

piloting at least one engine of the aircraft by a central controller ofthe device for assisting the piloting of an aircraft in taxiing in orderto apply the taxiing piloting command defined by the pilot,characterised in that the taxiing piloting command is an acceleration ordeceleration command of the aircraft, the central controller optionallyalso piloting at least one braking member of the aircraft in order toapply the acceleration or deceleration command defined by the pilot.

BRIEF DESCRIPTION OF THE FIGURES

The present disclosure will be better understood upon reading thefollowing description, given only as an example, and with reference tothe attached drawings, in which:

FIG. 1 is a schematic top view of an aircraft equipped with a firstaircraft taxiing piloting assist device according to the presentdisclosure;

FIG. 2 is a schematic depiction of a control member of the aircrafttaxiing piloting assist device of FIG. 1 ;

FIG. 3 is a flow diagram illustrating the activation and deactivation ofthe aircraft taxiing piloting assist device;

FIG. 4 is a schematic diagram illustrating the movement of the controlmember, when implementing an acceleration command of the aircraft, withrespect to a fixed neutral position;

FIG. 5 is a view similar to FIG. 4 , when implementing a decelerationcommand of the aircraft, relative to the fixed neutral position;

FIG. 6 is a view similar to FIG. 4 , when implementing a maximumacceleration command, to the point of reaching the aircraft's maximumtaxiing speed, relative to the fixed neutral position;

FIG. 7 is a view similar to FIG. 4 , when implementing a maximumdeceleration command of the aircraft, relative to the fixed neutralposition;

FIG. 8 is a similar view to FIG. 7 , when implementing a maximumaircraft deceleration command, using a control member detent; and

FIGS. 9-13 are views similar to FIGS. 4-8 , where the neutral positionis a movable neutral.

DETAILED DESCRIPTION

A first aircraft 10 provided with an aircraft taxiing piloting assistdevice 12 according to the present disclosure is schematicallyillustrated in FIG. 1 . The aircraft taxiing piloting assist device 12is preferably located in the cockpit of the aircraft 10.

The aircraft 10 comprises at least one propulsion engine 14, preferablyseveral propulsion engines 14, suitable for generating thrust of theaircraft 10. Each propulsion engine 14 is, for example, a jet engine ora turboprop.

The aircraft 10 further comprises wheels (not visible), at least onebraking member 16 associated with each wheel of the main gear, forslowing and stopping the aircraft 10 rolling on the ground, and at leastone actuating member 18 for the braking member 16, preferably arrangedin the cockpit of the aircraft 10.

Each propulsion engine 14 and each braking member 16 is adapted to becontrolled by the taxiing aircraft assist device 12 when the aircraft 10is rolling on the ground.

Thus, each propulsion engine 14 is controllable to vary a thrust forceon the aircraft 10, increasing or decreasing the mechanical energy ofthe aircraft 10 as it rolls. Each braking member 16 is adapted to act onat least one wheel of the aircraft 10, to slow down the rotation of thewheel, for example by friction, and to reduce the mechanical energy ofthe aircraft 10 as it rolls.

The aircraft 10 further comprises at least one current rolling speedmeasurement sensor and at least one display, preferably located in thecockpit, adapted to display a rolling speed value based on the data fromthe current rolling speed measurement sensor.

In a known manner, the aircraft 10 further comprises members 20 formodifying the drag of the aircraft. These members 20 comprisespeedbreaks, for instance.

With reference to FIGS. 1 and 2 , the aircraft taxiing piloting assistdevice 12 comprises at least one control member 30 adapted to beactuated by a pilot of the aircraft 10, from a neutral position, toapply an acceleration or deceleration command to the aircraft 10 duringtaxiing, and a central controller 32, adapted to pilot the or eachpropulsion engine 14 of the aircraft 10 and the or each braking member16 of the aircraft, in accordance with the taxiing acceleration ordeceleration command set by the pilot using the control member 30.

Advantageously, the aircraft taxiing piloting assist device 12 alsocomprises a light-up display system 34, capable of informing the pilotof the activation of the aircraft taxiing piloting assist device 12.

In the example shown in FIGS. 1 and 2 , the control member 30 is herecommon with that of a main system for managing controlling the variationof mechanical energy of the aircraft 10 during flight, as described inthe applicant's French patent application FR3058806.

The central controller 32 is then a flight central controller, capableof piloting each propulsion engine 14, and simultaneously eachmechanical energy modification member 20, in addition to each brakingdevice 16.

The aircraft taxiing piloting assist device 12 is then able to switchfrom an inactive configuration during the take-off, flight and landingphases of the aircraft 10 to an active configuration during taxiing.

In the inactive configuration of the aircraft taxiing piloting assistdevice 12, the control member 30 is adapted to be moved by the pilot tosend a command for varying the mechanical energy of the aircraft 10 tothe central controller 32, so that the central controller 32 controlseach propulsion engine 14 and each mechanical energy modification member20, without piloting each braking member 16.

The operation of the control member 30 and the control centre 32 in theinactive configuration of the aircraft taxiing piloting assist device 12is described in detail in French patent application FR3058806. It willnot be described in detail later.

In the active configuration of the aircraft taxiing piloting assistdevice 12, the control member 30 is adapted to be moved by the pilot toset an acceleration or deceleration command for the aircraft 10 duringrolling, intended for the central controller 32, so that the centralcontroller 32 pilots each propulsion engine 14 and each braking member16 to apply the acceleration or deceleration command.

As illustrated in FIG. 2 , the control member 30 comprises a support 40,a lever 42 movably mounted in the support 40 and at least one positionsensor 44 for measuring the position of the movable lever 42 relative tothe support 40.

The control member 30 further comprises an active system 46 for applyinga force on the movable lever 42, capable of returning the movable lever42 to a neutral configuration once the desired taxiing speed has beenreached and capable of creating respective maximum acceleration andmaximum deceleration stops 48A, 48B (visible in FIGS. 3 to 8 ), oneither side of the stroke of the movable lever 42.

The control member 30 further comprises at least one button 50 foractivating the active configuration of the aircraft taxiing pilotingassist device 12, and at least one button 52 for returning to theinactive configuration of the aircraft taxiing piloting assist device12.

Alternatively, the buttons 50, 52 are replaced by one or more buttons,for example located on the guidance panel or on a display screen of theaircraft 10.

Furthermore, an action by the pilot on the actuating member 18 of thebraking members 16 also causes the aircraft taxiing piloting assistdevice 12 to return to the inactive configuration. Advantageously, thisis also the case when activating another aircraft control mode, forexample a take-off mode (“TO mode”) or an automatic taxiing mode.

In this example, the support 40 is suitable for placement in the cockpitof the aircraft 10, preferably between the cockpit seats in the centrepylon.

As illustrated in FIG. 2 , the support 40 has an openwork base 54 and atop cover 56 mounted on the base 54 through which the movable lever 42is engaged.

The base 40 defines an interior volume 58 into which a lower part (notvisible) of the mobile lever 30 and the active force application system46 are inserted.

The top cover 56 closes the interior volume upwards by defining alongitudinal slide 60 for guiding the movement (rotation or translation)of the movable lever 42.

Advantageously, the slide 60 extends parallel to the longitudinal axisof the aircraft 10.

With reference to FIG. 2 , the movable lever 42 comprises a rod 62engaged through the slide 60, and a head 64 mounted at the upper end ofthe rod 62 for gripping by the hand of a user of the aircraft taxiingpiloting assist device 12, in particular a pilot. The head 64 herecarries the buttons 50, 52.

The movable lever 42 is adapted to be moved in the slide 60 relative toa neutral position. The movement of the movable lever 42 from theneutral position in a first direction (here forward) defines anacceleration command. The movement of the movable lever 42 from theneutral position in a second direction (here backwards), opposite to thefirst direction, defines a deceleration command.

In the example shown in FIGS. 4 to 8 , the neutral position is fixed.

The position sensor 44 is adapted to measure information representativeof the position of the movable lever 42 in the slide 60, and to transmitthe representative information to the central controller 32 at eachinstant so that the central controller generates a command to accelerateor decelerate the aircraft 10 acting on each propulsion engine 14 of theaircraft and/or on each braking member 16, as a function of thedifference gap between the current position of the movable lever 42 andthe neutral position.

The active force application system 46 comprises at least one actuatorand an actuator control unit connected to the central controller 32 forpiloting the force applied to the movable lever 42 and the movement ofthe movable lever 42 in the slide 60.

The active force application system 46 is, for example, adapted togenerate a force opposing the movement of the lever 42 when the pilotgrips the lever 42 and moves it, to resist the movement generated by thepilot.

The active force application system 46 is further able, once the pilothas released the lever 42, to generate a biasing force on the lever 42returning the lever 42 to the neutral position.

Furthermore, when the movement of the movable lever 42 with respect tothe neutral position corresponds to a maximum acceleration allowed bythe laws of the central controller 32, or to a minimum decelerationallowed by the laws of the central controller 32, the active forceapplication system 46 is suitable for creating a stop force,respectively materializing the maximum acceleration stop 48A or theminimum deceleration stop 48B on the stroke of the lever 42.

The central controller 32 is able, depending on the position of thelever 42 in the slide 60, to determine the desired acceleration ordeceleration command of the aircraft 10 during taxiing and to controleach propulsion engine 14 and/or each braking member 16 to apply thiscommand.

For example, the central controller 32 contains a correspondence tableor formula associating each movement of the lever 42, measured by theposition sensor 44, with an acceleration or deceleration value to becontrolled.

Thus, each movement of the movable lever 42 caused by the pilot awayfrom the neutral position towards the maximum acceleration stop 48Adefines an acceleration command that is applied by the centralcontroller 32, producing an increase in the speed of the aircraft 10, atthe commanded acceleration.

Each movement of the lever 42 caused by the pilot away from the neutralposition towards the maximum deceleration stop 48B defines adeceleration command that is applied by the central controller 32,producing a decrease in the speed of the aircraft 10, at the commandeddeceleration.

When the pilot releases the lever 42, a return to zero accelerationoccurs, and the central controller 32 maintains the current speed of theaircraft 10. The active force application system 46 returns the movablelever 42 to the neutral position.

In all cases, the pilot is able to observe the current speed of theaircraft as measured by the taxi rolling speed sensor on a cockpitdisplay.

Furthermore, the control unit of the active force application system 46is adapted to determine at each moment during rolling what is themaximum possible acceleration command of the aircraft 10, taking intoaccount the current speed of the aircraft 10, a predefined maximum speedthat the aircraft 10 can reach during taxiing (for example between 30knots and 50 knots, i.e. between 55 km/h and 92 km/h) and to modify theposition of the maximum acceleration stop 48A applied by the activeforce application system 46 according to the maximum possibleacceleration command that can be applied.

Furthermore, the active force application system 46 is adapted to movethe movable lever 42 from the current mechanical energy variationcontrol position (corresponding to the current thrust applied by eachengine 14) to the neutral position when the aircraft taxiing pilotingassist device 12 switches in the active configuration, and moving themovable lever 42 to the current position for controlling the variationin mechanical energy (corresponding to the current thrust applied byeach engine 14) when the aircraft taxiing piloting assist device 12switches to the inactive configuration.

The light-up display system 34 comprises, for example, at least onelight strip ramp 70 arranged in the vicinity of the control lever 42 anda control unit 72 for the or each light strip ramp 70, which is suitablefor displaying at least one light indication on at least one point onthe light strip ramp 70.

As illustrated in FIG. 3 , the control unit 72 is, for example, adaptedto display, on the light strip ramp 70, a first light indicationrepresentative of the activation of the aircraft taxiing piloting assistdevice 12 (see configuration (b) in FIG. 3 ), a second light indicationrepresentative of the current operation of the aircraft taxiing pilotingassist device 12 (see configuration (c) in FIG. 3 ), and a third lightindication representative of the deactivation of the aircraft taxiingpiloting assist device 12 (see configuration (d) in FIG. 3 ).

In this example, the first light indication consists of illuminating aplurality of points on the ramp 70 along the length of the slide 60. Thesecond light indication consists of illuminating only the positions ofthe stops 48A, 48B and the neutral position. The third light indicationconsists of the illumination of lamps on the ramp 70 from the maximumacceleration stop 48A to the current position of the movable lever 42.

A method of taxiing the aircraft 10 via the aircraft taxiing pilotingassist device 12 will now be described. This method is for examplecarried out implemented after the aircraft 10 has landed on a runway, inparticular after an automatic braking system during landing has beendeactivated. Alternatively, it is implemented from the aircraft parkingpoint to the take-off runway.

When the pilot wishes to use the aircraft taxiing piloting assist device12, he switches it to the active configuration, for example by pressingthe activation button 50 on the mobile lever 42.

In the example shown in FIG. 3 , the light-up display system 34advantageously displays the first light indication (see step (b) in FIG.3 ).

The active force application system 16 moves the movable lever 42 to theneutral position, represented by the dotted square in FIG. 3 .

The movable lever 42 thus remains at rest in this neutral position,which is advantageously marked by a local illumination of the ramp 70,according to the second light indication, as illustrated in step (c) ofFIG. 3 .

With reference to FIG. 4 , if the pilot wishes to move faster whentaxiing, he grips the movable lever 42, and moves it towards the maximumacceleration stop 48A, away from the neutral position (shown in dottedline) to set a desired acceleration of the aircraft 10 when taxiing.

The movement of the movable lever 42, and the established deviation fromthe neutral position then defines an acceleration command. The centralcontroller 32 receives the representative information from the positionsensor 44, and determines the acceleration command to be applied. Itthen controls the or each propulsion engine 14 to achieve the desiredacceleration. The speed of the aircraft 10 increases progressivelyfollowing the acceleration set by the command given by the pilot.

This avoids over-accelerating the aircraft 10 and maintains passengercomfort.

When the pilot is satisfied with the speed achieved, he releases thelever 42, and the acceleration decreases to a zero acceleration at whichthe central controller 32 maintains the current speed of the aircraft10.

As illustrated in FIG. 4 , the active force application system 46returns the movable lever 42 to the neutral position.

If the pilot wishes to apply a deceleration command instead, as shown inFIG. 5 , he moves the movable lever 42 towards the maximum decelerationstop 48B.

The movement of the lever 42, and the established deviation from theneutral position then defines a deceleration command. The centralcontroller 32 receives the representative information from the positionsensor 44, and determines the deceleration command to be applied.

The central controller 32 then acts on each brake member 16, and/or oneach propulsion engine 14, to achieve the desired deceleration. Thespeed of the aircraft decreases progressively following the decelerationset by the command given by the pilot.

When the pilot is satisfied with the speed achieved, he releases thelever 42, and the deceleration decreases to a zero acceleration at whichthe central controller 32 maintains the current speed of the aircraft10.

As illustrated in FIG. 5 , the active force application system 46returns the movable lever 42 to the neutral position.

In the example shown in FIG. 6 , if the pilot moves and holds themovable lever 42 to the maximum acceleration stop 48A, the maximumacceleration stop 48A remains fixed as long as the acceleration commandthus defined remains possible, taking into account the current aircraftspeed and the predefined maximum speed of the aircraft 10.

However, as the speed of the aircraft 10 approaches the predefinedmaximum speed, the active force application system 16 determines thatthe maximum possible acceleration command decreases and accordinglyconsequently moves the maximum acceleration stop 48A to the neutralposition, pushing the movable lever 42 to the neutral position.

When the preset maximum speed is reached, the maximum acceleration stop48A prevents the movable lever 42 from moving beyond the forward neutralposition.

Similarly, as illustrated in FIG. 7 , when the pilot wishes todecelerate sharply, he moves the movable lever 42 to the maximumdeceleration stop 48B, and holds it in that position, possibly until theaircraft 10 comes to a stop.

In the embodiment shown in FIG. 8 , the force activation system 46 isadapted to define a maximum deceleration stop 48B that is passable bythe pilot, and a detent 80 located beyond the maximum deceleration stop48B. When the pilot passes the maximum deceleration stop 48B, and placesthe lever 42 in the detent 80, the lever 42 remains held in the detent80, even if the pilot releases the lever 42, until the aircraft comes toa stop.

In the example shown in FIGS. 5 to 8 , the neutral position is a fixedneutral position. It corresponds to a fixed point on the slide 60, forexample in the middle of the slide 60.

In an embodiment illustrated in FIGS. 9 to 13 , the neutral position isa movable neutral position which moves along the slide 60 in accordancewith the current speed of the aircraft and the maximum possible rollingspeed predefined for the aircraft 10.

The movable neutral position between the maximum acceleration stop 48Aand the maximum deceleration stop 48B gives an indication of the currentspeed level in the permitted taxiing speed range [0; 50] knots, i.e.between 0 km/h and 93 km/h. The active force application system 46 locksthe movable lever 42 to the movable neutral position, even in theabsence of pilot action on the movable lever 42.

In the example shown in FIG. 9 , when the pilot moves the lever 42 toapply an acceleration command, the movement of the movable lever 42 islimited at the bottom by the position of the movable neutral and at thetop by the maximum acceleration stop 48A, which remains fixed.

The acceleration command set by the pilot with respect to the movableneutral position causes the central controller 32 to accelerate theaircraft 10 by maintaining the desired acceleration command, therebyincreasing the speed of the aircraft 10. The movable neutral positionthus gradually approaches the maximum acceleration stop 48A, as thecurrent speed of the aircraft increases.

When the rider pilot releases the movable lever 42, it is biased to thenew movable neutral position, which is different from the initialmovable neutral position, before the acceleration command has beenapplied.

The movable neutral position to which the movable lever 42 is returnedtherefore gives the pilot an immediate visual indication of the currentspeed value in relation to the permitted speed range.

The same applies during deceleration of the aircraft, as shown in FIG.10 , where the movable neutral position moves towards the minimumdeceleration stop.

In the example shown in FIG. 11 , when a maximum acceleration command isapplied by placing the movable lever 42 in abutment with the maximumacceleration stop 48A, the movable neutral position moves progressivelytowards the maximum acceleration stop 48A, until it reaches the currentposition of the movable lever 42 when no further acceleration can beapplied.

Similarly, in the example shown in FIG. 12 , when a maximum decelerationcommand is applied by placing the movable lever 42 in abutment with themaximum deceleration stop 48B, the movable neutral position movesprogressively towards the maximum deceleration stop 48B, until itreaches the current position of the movable lever 42 when no furtherdeceleration can be applied.

Furthermore, with reference to FIG. 13 , when a detent 80 is definedbeyond the maximum deceleration stop 48B, the movable neutral positionmoves to the maximum deceleration stop 48B, with the movable lever 42remaining in the detent 80.

In all of the above examples, the central controller 32 of the aircrafttaxiing piloting assist device 12 in the active configuration pilotseach engine 14 in its nominal thrust mode, advantageously without usingthe reverse thrust mode. Alternatively, the reverse thrust mode could beused.

Thanks to the aircraft taxiing piloting assist device 12 according tothe present disclosure, the accelerations and decelerations commanded bythe pilot are controlled, which has a very positive impact on thecomfort of the passengers, by avoiding the jolts of acceleration ordeceleration that occur when the pilot has difficulty in reaching thespeed he wishes to apply.

In addition, the pilot's workload is reduced, since a single controlmember 30, comprising a mobile lever 42 is used to pilot both thepropulsion engines 14 and the braking unit 16. Control is achieved byestablishing an implicit command to accelerate or decelerate, thecurrent speed being maintained once the pilot is satisfied with thespeed achieved and releases the lever.

In addition, the aircraft taxiing piloting assist device 12 is adaptedto maintain the aircraft 10 within a defined speed range by the presenceof the maximum acceleration stop 48A, which is movable in case of afixed neutral position, or is fixed when the neutral position ismovable.

In the examples just described, the aircraft 10 has no electric motor todrive a wheel of the aircraft, independent of the propulsion engines 14generating thrust for the aircraft. This makes the aircraft lighter,simplifies maintenance and reduces the risk of breakdowns.

In addition, there is no need for an additional device in the cockpit tocontrol the speed setpoint.

In another embodiment, the aircraft 10 is equipped with at least oneelectric motor suitable for driving a wheel of the aircraft,independently of the propulsion engines 14 generating thrust for theaircraft.

The aircraft taxiing piloting assist device 12 is then able to pilot theelectric motor and/or each braking device 16 to apply the accelerationor deceleration command defined by the control device command 30, ratherthan a speed setpoint, thereby improving passenger comfort.

In one embodiment, the control member 30 of the aircraft taxiingpiloting assist device 12 is an additional control member beyond themember that commands the aircraft's mechanical energy variation usedduring take-off, flight and landing.

In another embodiment, the control member 30 has no movable lever. Itincludes, for example, hardware or software acceleration anddeceleration buttons to control a movement of a cursor from a neutralposition.

A display shows a gauge with the cursor, the neutral position, and themaximum acceleration and minimum deceleration stops.

What is claimed is:
 1. An aircraft taxiing piloting assist devicecomprising: a control member operable by a pilot from a neutral positionto define a taxiing piloting command to control a speed of an aircraft;a central controller configured to pilot at least one aircraft engine toapply the taxiing piloting command defined by the pilot, the taxiingpiloting command being an acceleration or deceleration command of theaircraft during taxiing.
 2. The device according to claim 1, wherein thecentral controller is configured to additionally pilot at least oneaircraft braking member in order to apply the acceleration ordeceleration command defined by the pilot.
 3. The device according toclaim 1, wherein, after application of the acceleration or decelerationcommand and release of the control member, the control member isautomatically returned to the neutral position.
 4. The device accordingto claim 3, wherein the neutral position is a fixed neutral with respectto a stroke of the control member, the control member beingautomatically returned to the fixed neutral position.
 5. The deviceaccording to claim 3, wherein the neutral position is a movable neutralposition relative to a stroke of the control member, the control memberbeing automatically returned to the movable neutral position, or themovable neutral being movable to a current position of the controlmember.
 6. The device according to claim 1, wherein the control memberis configured to be moved to a maximum acceleration stop and/or to aminimum deceleration stop.
 7. The device according to claim 6, whereinthe maximum acceleration stop is configured to move along a stroke ofthe control member to limit the stroke of the control member as afunction of a current aircraft speed.
 8. The device according to claim6, wherein the minimum deceleration stop is configured to be overcome toreach a maximum deceleration detent in which the control member islocked in position.
 9. The device according to claim 1, wherein the atleast one aircraft engine is a propulsion engine of the aircraftexerting a thrust force on the aircraft, and/or wherein the at least oneaircraft engine is an electric motor to drive a wheel of the aircraft.10. The device according to claim 9, wherein the at least one aircraftengine is a jet engine or a turboprop engine.
 11. The device accordingto claim 9, wherein the control member comprises a movable leverconfigured to pilot the at least one aircraft engine to exert a thrustforce and/or wherein the control member comprises a movable lever topilot at least one aircraft drag modifier to reduce a mechanical energyof the aircraft, the device being configured to switch between aninactive configuration during take-off, flight and landing phases and anactive configuration during taxiing.
 12. The device according to claim11, in which, in the inactive configuration, the control member isconfigured to be moved by the pilot to send to the central controller acommand for varying the mechanical energy of the aircraft, so that thecentral controller pilots the at least one aircraft engine and the atleast one aircraft drag modifier, without controlling a braking memberof the aircraft, and wherein, in the active configuration, the controlmember is configured to be moved by the pilot to set an acceleration ordeceleration command for the aircraft during rolling, intended for thecentral controller, so that the central controller pilots the at leastone aircraft engine.
 13. The device according to claim 11, comprising anactivation button to switch the device in the active configuration,and/or a deactivation button to switch the device in the inactiveconfiguration.
 14. The device according to claim 13 wherein theactivation button or/and the deactivation button is arranged on themovable lever.
 15. The device according to claim 11, comprising alight-up display configured to produce at least one device activation,operation and/or deactivation luminous indicator.
 16. An aircraftcomprising: the device according to claims 1; and at least one aircraftengine for being piloted by the central controller in order to apply theacceleration or deceleration command defined by the control member. 17.The aircraft according to claim 16, comprising at least one brakingmember also configured to be piloted by the central controller to applythe acceleration or deceleration command defined by the control member.18. A method for taxiing an aircraft, implemented with an aircrafttaxiing piloting assist device, the method comprising: determiningactuation, by a pilot, of a control member of the device, from a neutralposition in order to define a taxiing piloting command; applying thetaxiing piloting command defined by the pilot with a central controllerof the device piloting at least one engine of the aircraft, the taxiingpiloting command being an acceleration or deceleration command of theaircraft.
 19. The method according to claim 18, wherein the centralcontroller further pilots at least one braking member of the aircraft toapply the acceleration or deceleration command defined by the pilot.